Verizon vs AT&T vs Sprint vs T-Mobile?

The best coverage depends on where you live. No carrier has decent coverage everywhere and they all lie about their coverage. The best way to really find out is to question friends, family and neighbors about which carrier they used and which they've been satisfied with. Once you know which carriers work in your area, you can look at plans and phones. Generally, Sprint is the cheapest with the worst coverage, followed by T-Mobile, AT&T and Verizon which generally has the best service and is the most expensive.